1. Using Analog Devices’ Blackfin for Embedded Processing Diana Franklin and John Seng

2. Outline Curriculum & Goals Blackfin Environment Expansion Board Lectures Labs Conclusions

3. Position in Curriculum 1 yr Dig des/ arch 1 yr Java EmbeddedAssemblyC Programming H&P except I/O and Parallel Processing Quarter system = 10 week terms

4. Goals CourseCurriculum Integration Financial TextbookAssembly unlike MIPS Inexpensive hardware Intuitive IDEParallelismUseful for several courses Breadboard access DSP

5. Outline Curriculum & Goals Blackfin Environment – Architecture – IDE – EZ-Kit Lite Board Expansion Board Lectures Labs Conclusions

6. Architecture

7. Basic Features 10 pipeline stages In-order core Separate data and pointer register files 1 instruction bank, 2 data banks Two each of Integer ALU, Multiplier, Accumulator, and Video units Two Data Address Generators

8. Interesting Features Circular Buffer support Reverse Bit Addressing Single-instruction Multiply-Accumulate Zero-overhead Loop Static Branch Prediction Can execute up to 3 instructions at a time, with limits on instruction types

9. Software Visual DSP++ Intuitive interface C or Assembly Programming

10. EZ-Kit Lite Board Basic board with buttons and LEDs as primary fun I/O devices No interface to a breadboard readily available

11. Goals satisfied Assembly unlike MIPS, but pipeline still simple Parallelism Powerful, usable for several courses DSP

12. Problems No textbook No interface to breadboard License server flakey for students Board has switches that change behavior – not a secure lab

13. Outline Curriculum & Goals Blackfin Environment Expansion Board Lectures Labs Conclusions

14. Expansion Board 24-pin cable (16 pins used)Buf Blackfin 3.3 Volts Breadboard 5 Volts 8 input bits, 8 output bits Voltage level Conversion buffer

15. Outline Curriculum & Goals Blackfin Environment Expansion Board Lectures Labs Conclusions

16. Decisions, Decisions The largest obstacle to class is now lecture preparation Copy / Pasting from Instruction Set Reference and Hardware Reference Manual time- consuming, not fun. We provide skeleton lectures plus the Blackfin-relevant information to integrate into your own lectures.

17. Textbook None available for Blackfin Generic textbooks are very high-level Ideal would be generic textbook with slides that add Blackfin-specific details – Wayne Wolf’s Computers as Components – Blackfin reference manuals

18. Normal Lecture Topics Memory-Mapped I/O / Polling Interrupts Timers Ports / Buses DMA and Power Analog / Digital Conversion

19. Extra Lecture Topics Blackfin ISA Blackfin Pipeline Blackfin Calling Convention Branch Prediction Parallel Processing C for Assembly Programs Code Optimization

20. Mixed Results We did not require (only suggested) generic textbook – Students found the lack of textbook difficult Additional Lectures added in second instantiation of course – Dramatically increased number of C programmers in lab. Tying to H&P textbook topics a positive reinforcement of earlier knowledge.

21. Outline Curriculum & Goals Blackfin Environment Expansion Board Lectures Labs Conclusions

22. Labs We include several labs. I can provide the sample code given to students if asked. Labs were multi-part to target specific lecture topics

23. Experience 10-weeks a short time to learn a new assembly language, new IDE, and so many new concepts Multi-part labs were difficult because starting a new project was high-overhead in this system Different theories on how much to give students (sample code vs nothing)

24. Outline Curriculum & Goals Blackfin Environment Expansion Board Lectures Labs Conclusions

25. Embedded processing classes must keep up with technology. Hardware is expensive, so cost sometimes overrides other factors. A repository of different architectures, tied to a generic textbook, might be useful.

26. Resources www.csc.calpoly.edu/~franklin/316/Bundle.tar